Husk Adhesion in Barley Grains

The barley grain at harvest is composed of a caryopsis enclosed in a husk. The husk is made up of two glumes, the palea on the ventral side and the lemma on the dorsal side. Both the lemma and the palea adhere to the surface of the pericarp. Husk adherence to the caryopsis is of considerable significance in both malting and brewing. If, in a batch of barley, there are grains with loose or detached husks these grains will germinate more rapidly than those with firmly adhering husks. Grains without husks are also likely to sustain embryo damage and give rise to mould growth. The consequences of poor husk adhesion or ‘skinning’ are uneven malting, loss of malting efficiency and lower malt production. Our current knowledge of husk adhesion is outlined below, with methods described in Hoad et al. 2003.